Connector arranged for conducting heat and high-frequency currents



Sept. l2, 1950 J. A. RADo CONNECTOR ARRANGED FOR CONDUCTING HEAT AND HIGH-FREQUENCY CURRENTS 2 Sheefs-Sheet 1 Filed Feb. 21, 194e Il '/ll/lllll INVETOR:

N A. RADO AT ORNEY.

Sept. l2, 1950 J. A. RADo 2,521,945 CONNECTOR ARRANGED FOR CONDUCTING n HEAT AND HIGH-FREQUENCY CURRENTS Filed Feb. 21, 1946 2 Sheets-Sheet 2 IN VEN TOR.'

RAD

RLY/V Patented Sept. 12, 1950 tCONNECTOR ARRAN-GED FOR iCONDUCTINGT HEAT AND HIGH-FREQUENCY `CURRENTS John A. Raab, Little Neck, N. Y., assigner, by mesne assignments, to Hazeltine Research, Inc., 1Chicago,lll., a corporation of Illinois Application February 21, 1946, Serial No. 649,345

l 11 Claims.

. 1 The present invention relates to electrical connectors and, particularly, to electrical connectors which are adapted detachably to engage electricallyf, conductive contact members that may be ducting electrical terminalfthereofv has a relatively;I large surface areafor1 engagement with a. correy spending surface areaon` the connector, and will be described kin thatconnection.

The power. outputdeveloped bysome high-fre--l quency oscillation generators and amplifiers is (ofi considerable magnitudaoften requiringthat one ormoreof `the electrode terminalsof the electronr tubes used therein have special constructionsfand shapes` adequately to dissipate kfrom the terminal the..heat developedn at the electrode due to elec-kv Otherwise the temperature f theelectrode or the glass sealat the electrode tron flow thereto` lead-.in conductor maybecome excessive and lcause failure of the glass.

cavity or coaxialline resonator.A This necessitates that the yheat developed at the lelectrodes readily be conducted therefrom,` through the medium of theelectrical terminal connectors, to the exterior of the cavity resonator wherev it is dissipated byv y radiation. This heat transfer` is generally effected byiproviding such electrode terminalswith large exterior.v surface areas for engagement with correspondingly large surface areas on the electrical connectors, thus enabling the latter to receive and rapidly conduct theheat away from the-tube.

.Prior connectors for4 use with; such terminals have @been provided with sufficiently large and firmlyzgengaging surfaces to 'afford a thermalconductive path of low thermal-resistance from the electron-tube terminal in; contactatherewith.

Experience has shown, however,l that `important electrical difficulties are encountered :with such. prior.,connectors when the `surfaces in .engage-l.A

ment alsorcornprise a portion of the conductive path of an electrical vcircuit ,offahigh-f-requency arrangement such as an oscillation generator or' amplifier. i

kAltlfiough the engagement ofsuch surfaces Vmay Frequently, however, such electron tubes are necessarily,mountedwithin a.

2 be sufficiently close to provide a good heat transfer,it generallyis not sufficiently intimate to afford an electrically conductive circuit path of definite effective path length and consistent low impedance for high frequency currents. Surface conditions such as slight irregularities on the faces of the engaging members, even though these members are constructed to close manufacturing tolerances, form irregular and unpredictable points of electrical contact therebetween which give rise to irregular and unpredictable effective path lengths for high frequency currents. Additionally, since the surface configurations of the terminals of individual tubes ordinarily vary somewhat, anengagement between an electrical connector and the terminal of a replacement tube in an electrical circuit may alter the effective electrical length of that circuit from its original value.

There is an additional difficulty with these prior connectors in that there is a tendency for corrosion, dust or other foreign matter to accumulate on the adjoining surfaces of an electrical connector and an electron-tube terminal of the character described above. These accumulations undesirably increase the resistance at the contacting surface area, particularly over a period of time. Furthermore, since the electrical and thermal circuits are completed by two large surface areas being brought into engagement over a large area,

any rfa-engagement of these surface areas, as by the replacement of an electron tube, leaves the undesirable surface condition on at least one of the surface areas substantially unaffected. Such surface conditions may undesirably` and unpredictablyy increase the effective resistan-ce of an electrical circuit which includes the engaging members.

When such anelectrical connector and the electron-tube terminal form a portion of a high-fre-` quency resonant circuit, there may result a lowered-or erratic Q for the resonant circuit due to the increased orunpredictable effective resistance last mentioned. kSince the Q of a resonant circuit may be defined as the ratio of the total energy in the circuit in a cycle of its operation to the energy dissipated in the cycle, it will be manifest that any increased effective resistance due to the engagement of the connector and tube terminal will increase the circuit losses and, hence, lower the Q of that circuit.

Ultra-short-wave oscillation generators and amplifiers which utilize prior electrical connectors with electron-tube terminals of the thermaleconducting type mentioned above are often,

subjected to undesirable frequency instability due in a considerable measure to the electrically conductive paths for high frequency currents being of unstable electrical lengths under operating conditions. Oscillation generators, for example, ordinarily employ one or more resonant transmission lines in the circuits thereof. The operating frequency of the generator is established by adjusting the electrical length of at least one of these transmission lines. These lines include in their effective electrical lengths the paths for the high-frequency electrical currents through' the connectors and tube terminals. ThusA when a high degree of tuning accuracy is required in a. generator of the type mentioned, the presence in the resonant transmission lines of electrical paths having unstable lengths. during the operation of the oscillation generator constitutes a serious disadvantage.

It is an object of the present invention, there- -fore to provide a thermally conductive electrical connector, of the type under consideration, which avoids one or more of the above-mentioned disadvantages and limitations of prior connectors ofthe type described.

It is a further object of the invention to provide a new and improved electrical connector, adapted detachably to engage an electrical contact member, having a greater thermal conductivity than has been heretofore readily obtainablewhile insuring an electrically conductive path of definite length and consistently low resistance for high-frequency wave-signal currents.

It is an additional object of the invention to provide a new and improved electrical connector, adapted detachably to engage an electrical contact member and to form therewith a portion of a high-frequency resonant circuit which, while insuring a thermal-conductive path of low thermal resistance, consistently maintains an electrically conductive path of` definite length and low..value of resistance for high-frequency electrical currents, thus contributing to a high figure of merit or Q for the resonant circuit.

In accordance with one form of the invention, a. thermally conductive electrical connector is adapteddetachably to engage an electrically conductivewcontact member and to form therewith a` portion of a high-frequency conductive circuit of critical electrical-length and resistance. The connector comprises a first thermally conductive member of relatively large mass for firmly yet detachably engaging the contact member over a substantial area thereof and to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which, in the conductive circuit, undesirably has an indefinitev path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of the members. The connector also includes a second electrically conductive member of relatively small mass for electrically yet detachably engaging the Contact member intimately over an area thereof smaller than the first-mentioned area to provide an electrically conductive path which, in the conductive circuit, has a definite length and consistently low value of resistance for the highfrequency wave-signal currents. The engagement of the connector and the contact member thus permits a substantial transfer of thermal energywhile establishing and maintaining in a definite and cons .nt manner the critical electrical length and resistance of the conductive circuit.

For a better understanding of the present in vention, together with other and further objects thereof, reference is had to the following description taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

Referring now to-the drawings, Fig. 1 illustrates a longitudinal sectional view of a high-frequency `wave-signal generator which utilizes a thermally conductive electrical connector embodying the present invention; Fig. 2 is an enlarged crosssectionalgview of that portion of the generator of Fig. l whichincludes the electrical connector of the present invention; Fig. 3 is a sectional view alongthe linel 3-5-3 lof Fig. 1; and Fig. 4 is a sectional view taken along the line 4-4 of Fig. l.

Referring now` more particularly to Fig. 1 of the drawings, the thermally conductive electrical connector of the present invention is illustrated in connection with a high-frequency wave-signal generator. This generator includes a triode electron tube lihaving suitable external terminals for the individual electrodes. The grid terminal comprises a grid radiator l5 of the type disclosed and claimed in Patent No. 2,439,641, granted April13, 1948 to Harold A. Wheeler, entitled An Arrangement for Conducting Heat and High Frequenoy Currents, and assigned to the same assigneeY as the instant invention. An annular anode terminal 29 and coaxially arranged heater and cathode terminals I6 and I1, respectively, to

be describedmore fully hereinafter, comprise the remaining terminals of tube vI 0.

The high-frequency signal generator also ine cludes an anode-grid cavity. resonator I9 comprising a, cylindrical hollow outer conductor 23' conductor 20 yis an annular metal disc 25 and a digitate electrically conductive contact member 26,4 which form elements of a thermally conductive electrical connector 21` embodying the present invention and hereinafter to be described in greater detail. A plurality of resilient fingers 6I .1 on the member 26 and also thefannular disc 23 engagethe anode terminal 23 of the trlode IIL The other end of the hollow cylindrical outer i conductor 20 4isclosed by a conductive disc 30 which is ,centrally apertured to receive a conductive cylindrical plunger 3| which slidably engagesa plurality of aligning, spring finger, electrical contacts 32,:32. Cylindrical plunger 3| has a diameter appreciably smaller than that of the hollow inner conductor 2l and effectively forms a re-.entrant portion of the outer conductor 23 axially movable for the purpose of tuning they cavity resonator I9.

The signal generator also includes an anodecathode cavity resonator 35 comprising a cylindrical hollow outer conductor 36 and a cylindrical hollow inner conductor 31, which are supported in fixed coaxial relationship by insulating spacers 38,38 secured between corresponding end walls 39- and 40 oftherespective inner and outer conductors. The outer conductor 36 is detachably secured to the outer conductor 20 o1' cavity resonator" I9 bya mechanical coupling arrangement 4I; the separable vfeature of the arrangement being: effective to permit the insertion of triode I0. The end of the outer conductor 36 supporting the couplingA arrangement 4I has attached thereto, by' means of suitable fasteners such as rivets 42 and by soldering a hollow electrically conductive member 43 which forms an additional portion ofelectrical connector 21. The member 43 has an inner 'and an outer set of resilient fingers 44, 44 and 45, 45, respectively (see also Fig. 4), which electrically and mechanically engage the anode terminal 29 of triode II) in a manner more fully to be described subsequently. The proximate end of innerconductor 31 is open to receive triode I0 while the end plate 39 at the opposite end of the inner conductor is apertured to receive and support a hollow conductive cathode post 41. An insulating'sleeve 48 maintains an inner conductor 49 in spaced coaxial relationship with the hollow cathode post 41. Attached to the cathode post 41 andthe inner conductor 49 is a coaxial connector having resilient fingers 50 and 5I for detachable lengagement with the respective cathode terminal I6 and the heater terminal I1 of triode III. Cathode post 41 and the inner conductor 49 extend outwardly through an aperture 52 in the end wall 40 of the outer conductor 36.

' yA lcoupling loop- 55, disposed in a position where the magnetic field in the cavity resonator I9 has a maximum value, is conductively secured to the anode disc 25 and is utilized to couple output signals of the oscillation generator to a suitable utilizing circuit 56, which may for example be an antenna. The connector 23 in the gridcircuit of triode I and the cathode post 41 are interconnected through a T-lter 51 and a grid-leak resistor 58. Filament excitation for the tube I0 is supplied by a transformer 6I, the secondary of which is connected to the cathode post 41 and the inner conductor 49 through secondary bifilar windings 59 of a bilar pulse-modulation transformer 60. The modulation transformer 60, as thus arranged, has its secondary winding 59 connected between the anode and -cathode of tube I0, and is connected with such polarity that each modulation pulse causes the cathode to be energized to a negative potential vrelative to the grounded anode.

The wave-signalgenerator described above is of a well-known type, the distributed inductance and capacitance of the cavity resonators I9 and 35replacing the conventional lumped components, `which are utilized in low frequency arrangements. The outer conductors and 36 of the oscillation generator and, hence, the

anode of triode I0 is maintained at ground potential. Cavity resonator I9 is preferably a half-wave re-entrant structure, while cavity lresonator 35, for optimum operation, should be 'slightly longer than one-quarter wave length at 'the mean operating frequency of the oscillation generator to afford a capacitive reactance.

Since the high-frequency wave-signal currents developed by the oscillation generator travel on the surface of the conductors, the conductive surfaces thereof are preferably silver plated to afford a low value of resistance.

Considering briefly the operation of the abovelvdescribed oscillation generator, excitation potentials for initiating oscillations are applied with negative polarity to the cathode of triode Ill from the modulation transformer 60. Oscillating voltages developed in the cavity resonator 35 as a resuit of oscillating cathode current flowing in this resonator are loosely coupled to cavity `resonator I9 through the control electrode-cathode capacitance of triode Il). The oscillation-signalvoltages developed at the control electrode end of cavity resonator I9 act to control `the cathode current of triode I'ul in the proper phase to sus-y tain the oscillation. Wave-signal energy is translated to the utilizing circuit 56 by means of y.loop

It is a characteristic of an oscillation generator of the type under consideration that the highI` frequency conductive circuits thereof have critical electrical lengths and resistances. It will thus be manifest that it is necessary to establish and maintain in a definite and consistent manner the electrical lengths and resistances of each portion of these circuits, including terminal connections to the electron tube,` in order to ensure satisfactory performance. Large quantities of heat are developed at the anode electrode of tube IIJ and, in order to limit temperature rise thereof, must be conducted away therefrom by the electrical connector 21 detachably engaging the anode terminal 29. At the same time, the connector 21. is included in the high-frequency cir. cuits of both of the cavity resonators I9 and 35. Additional problems are thus encountered as a result of the dual function of the electrical con` nector 21. For a clear understanding thereof, consider now with greater particularly the portion of the described oscillation generator which embodies the connector 21 ofthe instant inven-l tion, an enlarged axial sectional view thereof being illustrated in Fig. 2. of the drawings. vThe triode I0, employed in the generator, hasecoaxially arranged elements comprising an axially disposed cylindrical cathode II, a control electrode I2 in the form of a cage. and an outer cylindrical anode. I3. The control electrodek I2 and the cathode I I' are arranged in an evacuated enclosure comprising a glass envelope I4. The cylindrical anode has metal-to-glass seals with the envelope as indicated. The annular disc` 25 of electrical connector 21 comprises a first member which is adapted firmly to engage a contact member, comprising the anode terminal 29 of triode I0, over la substantial area thereof to provide a thermal-conductive path of low thermal resistance. The disc 25 also provides an electrical-conductive path which, in the conductive circuit of cavity resonator` I9, has an indefinite path length and value of resistance for high frequency wave-signal currents due to surface conditions at the areas of engagement of the annular disc 25 and the anode terminal 29. yA detailed explanation of the causes underlying the last statement regarding the indefinitenessof the effective path length -and resistance resulting from the engagement of annularvdisc 25 andthe anode terminal 29 will be presented subsequently;

Anode terminal 29 has a relatively large'mass and a high thermal conductivity substantially to assist in reducing the operating temperature of the anode electrode I3. For this purpose, the terminal 29 is provided with a relatively smooth flat surface area on the side which closely engages a corresponding surface area on the there mally conductive annular disc 25, thus affording effective conduction of heat therebetween.

In view of the previously mentioned indefinite electrical path length for high-frequency wavesignal currents which is undesirably provided by the annular disc 25 and the anode terminal 29, the electrical connector 21 also includes a second member comprising the digitate memberl which has. apluralityY of resilient fingers 65, 65. These fingers are individually adapted intimately to engagev the anode terminal 29 over an area thereof smaller than that area of annular disc.25 which is in mechanical and thermal engagement with `anode terminal 29. A skirt E6 on member 26 is secured to the outer conductor 2c by fasteners 61 and also is soldered thereto to ensure a low resistance connection. The intimate engagement of resilient fingers 65`with the anode terminal 29 causes the digitate member 26 to afford with certainty an electrical-conductive path which, in the oscillation-generator frequencydetermining circuit comprising cavity resonator I9 extending between the anode and control electrodes of triode I0, has a definite length and consistently low value of resistance for highfrequency wave-signal currents. The reasons for this will be explained more fully hereinafter. The free ends of ngers .65 extend radially inwardly for a short distance toward the axis of the oscillator, as represented in Fig. 3 of the drawings. When the tube I' is removed from engagement with the fingers 65, the latter proiect beyond the terminal-engaging surface of anode disc 25. The engagement of the fingers with terminal 29 thus is effective to force them radially inwardly, thereby providing a scraping or cleaning action between the tips of fingers 65 and the surface of substantially rigid anode terminal. 29. This ensures a good electrical connectionbetween the fingers and the terminal.

. Resilient fingers 45 of conductive member 43 on the other portion of electrical connector 21 are adapted to receive therebetween and engage the peripheral face of anode terminal 29, as illustrated in Fig. 2. Resilient fingers 44 are adapted to make a good electrical contact with the anode terminal 29 in a manner similar to that of the fingers 65. Since fingers 44 are in the conductive circuit of cavity resonator 35, it will be manifest that the. mechanical coupling means 4I and the conductive member 43 comprise means for maintaining the anode terminal 29 of tube I0 rmly in engagement with annular disc and the digitate nl member 26 while aiding in establishing a second electrical-conductive path of dente path length and consistent low value of resistance for highfrequency wave-signal currents. Resilient iingers 44 and 45 are also effective to support the tube I0 and orient the engaging surface of anode terminal 29 with respect to the corresponding surface of anode disc 25.

Reference is now made to Fig. 2 of the drawings for a consideration of the possible electrically conductive paths for high-frequency wave-signal currents through the portions of the detachable electrical connector. 21. For the purpose of explanation, portions of two such high-frequency current paths in the cavity resonator I9 are illustrated by broken lines and, for convenience, these portions are designated and will be referred t0 hereinafter as path A and path B. Path B represents a desirable path for radio frequency currents. Path A denotes an undesirable electrical path extending through the thermally conductive region. Paths such as path A are avoided by the connector of the instant invention.

At high frequencies, the current travel is on the surface or skin of a conductor rather than through the interior thereof as at lower frequencies. Path A illustrates the travel of radio frequency currents from the inner surface of cuter conductor 29 along the surface of annular disc 25 to some point C of satisfactory electrical contact members 25 and 29.

8 between the disc .25and the anodeterminalru, Path Acontinues from point C'valong onesuriace ofthe anodeterminal 29 to anode electrode f Il where the current follows the outer suriacetheroofprior to traversing the anode-cathode :space of tube I9. Point C is intended to representa surface irregularity, such as a high spoton either or both of the engaging members 25 and 29. ora clean low resistance spot between them. It will be manifest that the exact location of spot C on the relatively large, flat, engaging surfaces of members 25 and29 will be unpredictabledueto the random disposition of small surface irregularities and accumulations of foreign matter on the abutting surfaces. The frequency of .the high-frequency resonantcircuit comprisingy cavity resonator I9depends upon the effective electrical length of the transmission line including the outer and inner conductors 20 and 2| and the anode and control-electrode terminal connections associated therewith, Hence, a slight variation 1n the electrical length of this conductive circuit, as with tube changes or due to mechanical vibration of the generator, may result in an appreciable change in operating frequency of the generator. It may also be noted that while the effective high frequency current path includes the point C, the resistance presented by that point may have a higher value than is desired due to corrosion or other surface accumulations on the engaging This value of resistance may impair the figure of merit or Q of the cavity resonator I9 since the energy dissipated during each alternating current cycle is increased with any such increase of contact resistance. Hence, path A undesirably has an indefinite path length and indefinite value of resistance for high frequency currents. It is imperative for adequate stability of operating frequency and operating characteristicsof the generator that an electrically conductivepath .in any portion of the conductive circuit of ycavity resonator I9, particularly the conductive pathybetweenouter conductor 20 and the anode terminal 29,',have a definite length and definite ixnpedance during the operation of the arrangement.

Digitate member 26 with its resilient ngers 65 affords the shorter electrically conductive path B as previously mentioned, the fingers 65 provide a scraping or self-cleaning action each time they newly engage the anode terminal 29. Path B, therefore, has a definite length and consistently low value of. resistance for high frequency currents. These characteristics are enhanced by the fact that the tips of resilient fingers 65 contact but a small portionof the area of anode terminal 29. Since path A is considerably longer than path B, the higher inductance of the former causesthe major portion of high frequency currents to: follow path B. Because the engaging regionfbetween the fingers 65 and anode terminal 29 isz always definitely known, the electrical connector21 establishes and maintains in a consistentmanner several desirable electrical characteristicsof the cavity resonator I9, namely, frequency stability anda high Q. At the same time, the connector 21 conducts large amounts of thermal energy to the'heat-dissipating outer conductors 20 and 36.

It will be clear from the foregoing explanation that the resilient conductive fingers 44 of member 43 in the conductive circuit of cavity resonator Il serve a function similar to that of the resilient fingers 65 on the digitate member 26. The combined effect of the several portions of the electrical connector results in improved performance by the high-frequency oscillation generator associated therewith. Fingers 4'4 have the additional important function of biasing the anode terminal 29 into firm engagement with the annular disc 25 and the contact fingers 65 to ensure that the latter consistently have the desirable characteristics last described.

While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from' the invention, and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

l. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact member and to form therewith a portion of a high-frequency conductive circuit of critical electrical length and resistance comprising, a first thermally conductive member of relatively large mass for firmly yet detachably engaging said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a second electrically conductive member of relatively small mass for electrically yet detachably engaging said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistance for said high-frequency wave-signal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

2. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact member and to form therewith a portion of a high-frequency conductive circuit of critical electrical length and resistance comprising, a first thermally conductive and substantially rigid member of relatively large mass for firmly yet detachably engaging said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a second electrically conductive resilient member of relatively small mass for yieldingly yet detachably engaging said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistancev for said high-fre- 'quency wave-signal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween while establishingv and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

3. A thermally conductive electrical connector adapted detachably to engage a relatively smooth surface on an electrically conductive contact member and to form therewith a portion of a high-frequency conductive circuit of critical electrical length and resistance comprising, a first thermally conductive member of relatively large mass having a relatively smooth surface area for firmly yet detachably engaging a corresponding relatively smooth surface area on said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a second electrically conductive member of relatively small mass for electrically yet detachably engaging said relatively smooth surface area on said contact member intimately over an area thereof smaller than said first-mentioned .area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistance for said high-frequency wavesignal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

4. A thermally conductive electrical connector adapted detachably to engage a relatively fiat surf-ace area on an electrically conductive contact member and to form therewith a portion of a high-frequency conductive circuit of critical electrical length and resistance comprising, a first thermally conductive member of relatively large mass having a relatively flat surface area rfor firmly yet detachably eng-aging a corresponding relatively fiat surface area on said contact member over a substantial area, thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a second electrically conductive member of relatively small mass for electrically yet detachably engaging said relatively fiat surface area on said contact member intimately over an area thereof' smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistance for said high-frequency wavesignal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

5. A thermally conductive electrical connector adapted detachably to engage an annular electrically conductive contact member and to form therewith a portion of a high-frequency conductive circuit cf critical electrical length and resistance comprising, an annular rst thermally conductive member of relatively large mass for firmly yet detachably engaging said contact member @Ver a Substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a digitate electrically conductive second member of relatively small mass for electrically yet detachably engaging said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistance for said high-frequency wave-signal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

6. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact member and to form therewith portions of a plurality of high-frequency conductive circuits of critical electrical lengths and resistances comprising, a first thermally conductive member of relatively large mass for detachably engaging said contact member over a substantial area thereof to provide a thermalconductive path of low thermal resistance and electrically conductive paths which in said conductive circuits undesirably have indefinite effective path lengths and values of resistance for said high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, second and third electrically conconductive members of relatively small mass for electrically yet detachably engaging said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in an individual one of said conductive circuits has a definite length and a consistently low value of resistance for said high-frequency wave-signal currents, and means including said third member for maintaining said Contact member firmly in engagement with said first and second members, whereby t e engagement of said connector and said contact members permits substantial trans-- fer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical lengths and resistances of said conductive circuits.

7. A thermally conductive electrical connector adapted detachably to engage an electrically ccnductive Contact -member and to form therewith portions of a plurality of high-frequency conductive circuits of critical electrical lengths and resistances comprising, a first thermally conductive member of relatively large mass for detachably engaging said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and electrically conductive paths which in said conductive circuits undesirably have indefinite effective path lengths and values of resistance for said highfrequency wave-signal currents due to surface conditions at the areas of engagement of said members, second and third electrically conductive members of relatively small mass for elec-- trically yet detachably engaging said Contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in an individual one of said conductive circuits has a definite length and a consistently low value of resistance for said high-frequency wave-signal currents, and means including said third member for orienting and maintaining said contact member firmly in engagement with said first and second members, whereby the engagement of said connector and said contact members permits substantial transfer of thermal energy therebetween While establishing and maintaining in a definite and consistent manner said critical electrical lengths and resistances of said conductive circuits.

8. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact disc and to form therewith a portion of a high-frequency conduct-ive circuit of critical electrical length and resistance comprising, a first thermally conductive member yof rela.- tively large mass for detachably engaging one face of said contact disc over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wavesignal currents due to surface conditions at the areas of engagement of said members, a second electrically conductive member of relatively small mass for electrically yet detachably engaging one face of said contact disc intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a definite length and consistently low value of resistance for said high-frequency wave-signal currents, and means engaging the periphery and the other face `of said contact disc for orienting said one face of said contact disc with respect to said first and second members and for maintaining a firm engagement between said contact disc and said members, whereby the engagement of said connector and said contact disc permits substantial transfer'of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said conductive circuit.

9. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact member and to form therewith a portion of a high-frequency resonant circuit of critical electrical length and resistance comprising, a first thermally conductive member of relatively large mass for firmly yet detachably engaging said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said resonant circuit undesirably has an indefinite effective path length and value of resistance for high-frequency wavesignal currents due to surface conditions at the area of engagement of said members, and a second electrically conductive member of relatively small mass for electrically yet detachably engagingr said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said resonant circuit has a definite lengthand consistently low value of resistance for said highfrequency wave signal currents, whereby the engagement of said connector and said contact member permits a substantial transfer of thermal energy therebetween While establishing and maintaining in a definite and consistent manner 13 the electrical characteristics of said resonant circuit.

10. A thermally conductive electrical connector adapted detachably to engage an electrically conductive contact member and to form therewith a portion of a high-frequency cavity resonator of critical electrical length and resistance comprising, a first thermally conductive member of relatively large mass for detachably engaging said contact member over a substantial area thereof to provide a thermal-conductive path of low thermal resistance to the exterior of said cavity resonator and an electrically conductive path which in said cavity resonator undesirably has an indefinite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said members, and a second electrically conductive member of relatively small mass for electrically yet detachably engaging said contact member intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said cavity resonator has a definite length and consistently low value of resistance for said high-frequency Wave-signal currents, whereby the engagement of said connector and said contact member permits substantial transfer of thermal energy therebetween and to the exterior of said cavity resonator while establishing and maintaining in a definite and consistent manner said critical electrical length and resistance of said cavity resonator.

11. A thermally conductive electrical connector adapted detachably to engage an electrical terminal of an electron tube and to form with said terminal a portion of a conductive circuit of critical electrical length and resistance in a high-frequency wave-signal translating arrangement comprising, a first thermally conductive member of relatively large mass for detachably Cil engaging said terminal over a substantial area thereof to provide a thermal-conductive path of low thermal resistance and an electrically conductive path which in said conductive cir-A cuit undesirably has an indeilnite effective path length and value of resistance for high-frequency wave-signal currents due to surface conditions at the areas of engagement of said terminal and said member, a second electrically conductive member of relatively small mass for electrically yet detachably engaging said terminal intimately over an area thereof smaller than said first-mentioned area to provide an electrically conductive path which in said conductive circuit has a denite length and a consistently low value of resistance for said highfrequency wave-signal currents, and means for supporting said tube and for maintaining said terminal rmly in engagement with said first and second members, whereby said engagement of said connector and said terminal permits a substantial transfer of thermal energy therebetween while establishing and maintaining in a definite and consistent manner said critical electrical length an'd resistance of said conductive circuit in said wave-signal translating arrangement.

JOlI-IN A. RADO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,167,201 Dallenbach July 25, 1939 2,353,742 McArthur July 18, 1944 2,408,355 Turner Sept. 24, 1946 2,411,522 Chevigny Nov. 26, 1946 2,423,548 Bels July 8, 1947 2,439,641 Wheeler Apr. 13, 1948 

